Russell truly believed he was living in the time of the rapture. It seemed to me that guy was just trying to understand the Bible better which is why he didn't mind meeting with those who had differing viewpoints. Pretty much it was a bunch of people from various protestant groups throwing ideas and dates around.
I don't think he was actally trying to lead anything. Also, he could be questioned about a particular belief.
WTBTS is embarrassed by his means of calculations and that whole pyramid fixation. Although, Egyptology was all the rage back then. Even the Mormons claimed being chosen from some ancient Egyptian writings given to them by an apparently non English literate angel.
Now Rutherford, he was the arrogant one that claimed the group was "chosen", came up with using what's thought to be God's name (even Jesus didn't do that), began to degrade other Christian groups, and to set up the monster which cannot be questioned.